Protective coatings are applied to food and beverage containers (e.g., cans) to prevent the contents from coming into contact with the container's metal surface. Contact of the container contents with the metal surface (e.g., the interior), especially where acidic products such as soft drinks, tomato juice or beer are involved, can lead to metal container corrosion and result in container content contamination and deterioration. Protective coatings are also applied to the interior of food and beverage containers to prevent corrosion in the container headspace between the food product fill line and the container lid, which is particularly problematic with high salt content food products.
Multi-coat coating systems that have been used to coat the interior of food and beverage containers typically contain an epoxy resin incorporating bisphenol A (BPA) cross-linked with a phenolic resin.